In pneumatic tires, cavernous resonance caused by the vibration of air that the tire is filled with is one cause of noise being generated. When a tire is rolled, uneven treading surfaces cause a tread portion to vibrate. The vibrations of the tread portion cause the air inside the tire to vibrate which causes cavernous resonance to be generated.
As a way to reduce the noise caused by this cavity resonance, it has been proposed that a sound-absorbing member be provided within the cavity between the tire and the rim of the wheel. More specifically, a strip-shaped sound-absorbing member is bonded to a region of the tire inner surface corresponding to the tread portion (for example, see Japanese Unexamined Patent Application Publication Nos. 2002-67608A and 2005-138760A).
However, radial growth is produced by centrifugal force during high-speed traveling, so this produces a shear strain in the bonding surface of the sound-absorbing member. Then after the bonding surface of the sound-absorbing member that is bonded to the tire inner surface has been subjected to shear strain repetitively over a long period of time, the problem of peeling of the sound-absorbing member from the tire inner surface can occur.
Also, in the pneumatic tire, a plurality of belt layers is disposed on the outer circumferential side of the carcass layer in the tread portion, and a belt cover layer made from organic fiber cords oriented in the tire circumferential direction is disposed on the outer circumferential side of these belt layers, so the high-speed durability is increased. Aliphatic polyamide fiber cords as typified by nylon fiber cords are widely used as the organic fiber cords of this type of belt cover layer. However, although nylon fiber cords are excellent from the cost point of view, they cannot necessarily sufficiently withstand the shear strain of the tire inner surface produced by centrifugal force during high-speed traveling, so at present they are unable to reduce peeling of the sound-absorbing member.